Facebook IPO:

• Zuckerberg snaps photo of desk; new Facebook layout 'leaked'?

• Facebook's Timeline: All my favorite mistakes, organized.

• Facebook’s S-1 reveals: 845 million users every month, more than half daily, half mobile.

• In China, Facebook alternatives thrive.

• Does Facebook have a mobile problem?

Social Media:

• Blogging site Tumblr makes itself the news.

Mobile Marketing:

• Google mobile search ad requests more than doubled in 2011.

Online Ad Industry:

• Viacom’s profit drops 65% as advertising falls.

Mobile Computing:

• How Microsoft could lose its grip on 'rugged' devices.

Search:

• Yahoo releases search engine dedicated to iPhone and Android apps.